Reasons for unfavorable results of surgical treatment of diaphyzary fractures of bones of the forearm.

The article provides a retrospective analysis of the causes of complications of surgical treatment of diaphyseal fractures of the forearm bones.В статье проводится ретроспективный анализ причин осложнений оперативного лечения диафизарных переломов костей предплечья

REMOVAL OF MINERAL IMPURITIES FROM AFTER - HARVESTING RESIDUES OF CORN

Due to the energy crisis, special attention is paid to the production and use of biofuels. After-harvesting residues of corn (AHRC) may become a perspective source of energy for grain dryers. The following components of the AHRC are distinguished: stem, leaves, rod and wrapper of the cob. The AHRC is about 55...60% of the total weight of the plant. The annual harvest of corn grain is more than 20 million tons. The calorific value at burning of wheat straw is 14.4 MJ/kg, AHRC -15.7 MJ/kg. For comparison, the calorific value of wood on average is 14.24 MJ/kg, and natural gas is 33.5 MJ/m3 [1]. Using the AHRC can significantly reduce the need for imported gas. One of the directions of the use of plant raw materials as fuel is the production of granules [2]. The technology involves purifying raw materials from impurities, crushing and granulation. For a similar scheme, granulated feeds are produced. When picking up a harvester, following transportation and reloading, various contaminants, including mineral impurities in the form of stones, fall into the green mass. Having hit the crusher stones lead to damage to parts of the crushing mechanism, an accident and even an explosion. Clearing straw from impurities in agriculture is carried out on pneumatic separating machines [3]. But in the technical literature there is no data available to the separation of mineral impurities from the AHRC. As a result of the experiments, it was found that leaves and stalks can be separated by air from large stones, and the separation of rods from stones is complicated. Under the influence of air flow, the rods are rotated along the pneumatic separating canal and unfolded by a long axis in parallel with the air flow, which leads to a decrease in the area of the midel section and to the reduction of the aerodynamic resistance. Therefore, to provide the required force acting on the core from the air stream, they increase the air velocity, which causes the capture and joint movement of the stones. To improve the separation process of the AHRC from the stones, it is necessary to develop a nutritional mechanism of the separator, in which to predict the possibility of orientation of the rods in the pneumocaps to the long axis across the air flow. This will enable you to reduce the air velocity required for separation and increase the difference in aerodynamic forces acting on the stones and rods. Accordingly, at the same time, the energy intensity of the pneumatic separation process will decrease and the efficiency of separating the AHRC from the stones increases. The separation of small stones smaller than 3 mm only by air is impossible, since they are picked up by the air flow that moves at the speed necessary for separating the stems (7.5...12.5 m/s). For the separation of small stones, it is proposed to use grid separators with combined air purge. For the complete separation of mineral impurities from corn cores, it is recommended to use hydro-separators

Modification of REE distribution of ordinary chondrites from Atacama (Chile) and Lut (Iran) hot deserts: Insights into the chemical weathering of meteorites

The behavior of rare earth elements (REEs) during hot desert weathering of meteorites is investigated. Ordinary chondrites (OCs) from Atacama (Chile) and Lut (Iran) deserts show different variations in REE composition during this process. Inductively coupled plasmaâ\u80\u93mass spectrometry (ICP-MS) data reveal that hot desert OCs tend to show elevated light REE concentrations, relative to OC falls. Chondrites from Atacama are by far the most enriched in REEs and this enrichment is not necessarily related to their degree of weathering. Positive Ce anomaly of fresh chondrites from Atacama and the successive formation of a negative Ce anomaly with the addition of trivalent REEs are similar to the process reported from Antarctic eucrites. In addition to REEs, Sr and Ba also show different concentrations when comparing OCs from different hot deserts. The stability of Atacama surfaces and the associated old terrestrial ages of meteorites from this region give the samples the necessary time to interact with the terrestrial environment and to be chemically modified. Higher REE contents and LREE-enriched composition are evidence of contamination by terrestrial soil. Despite their low degrees of weathering, special care must be taken into account while working on the REE composition of Atacama meteorites for cosmochemistry applications. In contrast, chondrites from the Lut desert show lower degrees of REE modification, despite significant weathering signed by Sr content. This is explained by the relatively rapid weathering rate of the meteorites occurring in the Lut desert, which hampers the penetration of terrestrial material by forming voluminous Fe oxide/oxyhydroxides shortly after the meteorite fall